Design of high output broadband piezoelectric energy harvester

Designing a wideband vibration based piezoelectric energy harvester is a challenging problem. This paper presents a technique to increase the operating frequency range and to enhance the amplitude of the generated voltage. The harvester is designed with a propped cantilever beam with variable overhang having step sections. The harvester is modeled using Euler Bernoulli beam theory. The wider operating frequency range is achieved by varying the overhang length and the enhancement in the magnitude of the generated voltage is achieved by introducing step sections in the beam. Further the magnitude of the generated voltage is found to increase with the reduction in step thickness. The performance of the energy harvester like bandwidth, voltage generated and power harvested obtained from analytical model are in close agreement with experimental results.